1. Field of the Invention
The present invention relates to a process for supplying fuel to an internal combustion engine intended to equip a motor vehicle. The present invention relates more particularly to a process for supplying fuel that is suited to the starting phase of the engine. The invention also relates to an internal combustion engine suited to the use of the process.
2. Discussion of the Related Art
The standards relating to pollution and to fuel consumption of motor vehicles equipped with internal combustion engines become stricter every day. The automobile industry today is therefore occupied with finding technical solutions to respond to these requirements without overly restricting the performance of the vehicles or affecting their cost.
It is known to reduce fuel consumption and the emissions of pollutants of engines, by manipulating the supply of fuel of the combustion chambers due to an electronic fuel injection device comprising one or more electronic injectors placed on the intake circuit of the combustion air, and an electronic control system which calculates and controls the flow rate of the injector or of the various injectors from values taken from a certain number of operating parameters of the engine.
However, in certain circumstances and particularly during cold-starting phases, the liquid fuel injected is mixed poorly with the combustion air and is condensed on the walls of the intake pipes. It is then necessary to greatly increase the richness of the aspirated mixture to assure the starting of the engine, which causes an excess consumption of fuel and a high emission of polluting substances.
Various systems have been developed to eliminate these drawbacks and to speed up the vaporization of the fuel during the starting phase. It is possible to cite, for example, air blanket injectors where an auxiliary air jet sprays the fuel at the outlet of the injector nose, or heating resistors of the PTC type placed in the intake manifold to cause the vaporization of the fuel. These various devices are, however, costly, difficult to maintain and difficult to control.